The present invention relates to a drive element for a load carrier of an overhead conveyor system, and more particularly to a drive element for driving rail-guided load carriers of an overhead conveyor system which travel on rollers, particularly for driving a single-track conveyor carriage provided with articles of clothing hanging on hangers.
In a conventional overhead conveyor system, a drive element is fastened to a conveyor means (a drive chain) extending above a runway rail and parallel thereto. The conveyor means has a driver which, in its active position, acts during the transport for the transmission of force to the load carriers and is pivoted to the drive element by means of a horizontal pin in a hole provided the drive element. The driver is swingable out of its active position in the direction of transport (T) and is substantially rigid in the direction opposite the direction of transport (T).
In particular in the clothing industry, the articles of clothing suspended from clothes hangers are hung, for purposes of filling orders or removal, on the carrier rod of the single-track conveyor carriages, so-called trolleys, of an overhead conveyor system. Each of the trolleys, which travel on rails, is pushed by a driver which acts on the front track roller. The driver is developed on a drive element which, in its turn, is fastened on the drive chain which is arranged above the runway rail.
In order for a trolley to be properly transported, the driver must be rigid in the direction of transport. However, in order to be able also to pass by the trolley, the driver is swingable in the direction of transport and can thus be moved over the rollers of the trolley when a trolley is not being transported.
In this connection, it is known to fasten the driver, which is formed of plastic, to the drive element by means of a pin which is passed horizontally and eccentrically through one end of the driver. By this asymmetrically arranged axis of swing of driver, the swingability permissible in only one direction is obtained.
If a trolley in the conveyor line is unintentionally prevented from traveling further by coming against an obstacle, for instance, or by the rear track roller by error leaving the track at a switch while the front track roller continues to remain in the conveyor line, then either the drive element, the driver, or even the entire conveyor system will be inescapably damaged since the drive chain rotates continuously.